You're surprisingly vulnerable to negative thinking when you're doing something that's practically second nature to you, says psychiatrist Rebecca Gladding, MD, coauthor of You Are Not Your Brain
. When you're in the flow—say, knitting another scarf—the brain's prefrontal cortex, which handles executive function, kicks back and lets the basal ganglia, or the habit center, take over. This is when the toxic thought sneaks in and gains control, while your knitting needles continue to clack away rhythmically. Get your prefrontal cortex to refocus by turning your attention to a challenging activity that requires your full attention, like listening to Coffee Break French podcasts
, playing Words With Friends with a responsive pal or cooking (only if you aren't a gourmet chef). Gladding says that it's important to do this quickly, because the more time you spend dwelling on things, the stronger those mental pathways become. "Then every time you get anxious, you'll automatically switch into obsessive mode," she says—and that's something you definitely want to avoid.
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